Thioxanthene Thiothixene

Thioxanthene Thiothixene Very high High Medium Medium Medium... 

Antipsychotic drugs currently approved for clinical use in the United States are summarized in Table 10.1. Drugs classified as typical include the following several phenothiazine derivatives (1-9), the thioxanthene, thiothixene (10), the butyrophenone, haloperidol(ll),... 

Thioxanthenes thiothixene chlorprothixene intermediate less sedation, extrapyramidal effects, decreased risk of TD... 

The answer is b. (Katzung, p 4822) Haloperidol, a butyrophenone, is by far the most likely antipsychotic to produce extrapyramidal toxicides Other agents, such as piperazine (an aromatic phenothiazine), thiothixene (a thioxanthene), and pimozide (a diphenylbutyropiperidine) are comparitively less likely to produce extrapyramidal toxicity than haloperi-dol. The antagonism of dopamine in the nigrostriatal system might explain the Parkinson-like effects Both haloperidol and pimozide act mainly on D2 receptors, whereas thioridazine and piperazine act on ooadrenergie receptors, and have a less potent but definite effect on D2 receptors. 

Whatever the underlying causes may be, neuroleptic medications are the most effective treatment for schizophrenia. All antipsychotic medications have some form of dopamine receptor antagonism and they are distinguished by their chemical class. The phenothiazines include chlorpromazine (Thorazine), thioridazine (Mellaril), mesoridazine (Serentil), trifluoperazine (Stelazine), fluphenazine (Prolixin), and prochlorperazine (Compazine). The thioxanthenes include chlorprohixine (Taractan) and thiothixene (Navane). Butyrophenones are represented by haloperidol (Haldol). Loxapine (Loxitane) is a dibenzoxapine, and molindone (Moban) is a dihydroindolone. 

Phenothiazines are classified on fhe basis of fheir chem-isfry, pharmacological acfions, and pofency. Chemical classifications include the aliphatic (e.g., chlorproma-ztne T/iorazme), piperidine (e.g., thioridazine Me//an7), and piperazine subfamilies. The piperazine derivatives are generally more potent and pharmacologically selective than the others. The thioxanthenes (e.g., thiothixene Navane) are chemically related to the phenothiazines and have nearly equivalent potency. The... 

Thioxanthene derivatives flupenthixol decanoate flupenthixol dihydrochloride thiothixene zuclopenthixol acetate zuclopenthixol decanoate zuclopenthixol dihydrochloride... 

Thioxanthenes are related to the phenothiazines and act at DA receptors. Examples of this structural class are chlorprothixene and thiothixene. 

Steriin C, Ban TA, Jarroid L. The piace of thiothixene among the thioxanthenes. Curr Ther Res Ciin Exp 1972 f4 205-f4. 

Thioxanthenes are used in the treatment of psychosis, including schizophrenia, senile psychosis, pathological jealousy, and borderline personality disorder. Other uses include the treatment of pain, postoperative neuralgia, sedation, anxiety neurosis, childhood behavior problems, and depression. The maximum therapeutic daily oral dose for chlorprothixene, flupenthixol, and thiothixene is 600, 224, and 60 mg respectively the maximum intramuscular dose of each is 200 mg day 100 mg weekly, and 30 mg dayrespectively. Some thioxanthenes and thioxanthenones have shown signs in mice and in vitro assays of possible human therapeutic potential against tumors, and some thioxanthenes have been shown to have cytotoxic and antimicrobial activities. 

Thiothixene (99) is the only thioxanthene de- rivative that continues to be marketed for the treatment of psychotic disorders in the United... 

Navane [Pfizer]. TM for the cis isomer of iV,iV-dnnethyl-9[3-4-methyl-l-piperazinyl-pro-pylidene]-thioxanthene-2-sulfonamide. An antipsychotic drug (thiothixene) said to be as effective as most of the phenothiazines. Approved by the FDA. 

Phenothiazine derivatives (e.g., chlorpromazine) Thioxanthene derivatives (e.g., thiothixene) Butyrophenone derivatives (e.g., haloperidol) Dihydroindolone derivatives (e.g., molindone) Dibenzoxazepine derivatives (e.g., loxapine) Atypical neuroleptics (e.g., sulpiride, pimozide, and clozapine)... 

Thiothixene (2 mg t.i.d. in mild cases) is indicated in the management of psychotic disorders. Thiothixene and chlor-prothixene are thioxanthene antipsychotics. Their select pharmacological properties are compared with chlorprom-azine and haloperidol and are shown in Table 2. 

Haloperidol is a member of the butyrophenone class of drugs. It thus has greater potency and less autonomic effects than thiothixene, a member of the thioxanthene class of antipsychotics. 

A. Classification The major chemical subgroups of antipsychotic drugs are the phenothiazines (eg, chlorpromazine, thioridazine, fluphenazine) the thioxanthenes (eg, thiothixene) and the butyrophenones (eg, halopeiidol). 

The psycholeptic action, characteristic of these phenothiazines, was later found in other series, notably among the thioxanthenes [e.g. chlor-prothixine (75.74), Taractan ], and the phenylbutyrophenones introduced by Janssen in Belgium about 1958 [e.g. haloperidol (75.75)]. To-day a distinction is made between the high-dose psycholeptics, such as chloro-promazine and chlorprothixen, which have an additional sedative effect, and the low-dose psycholeptics, such as perphenazine, trifluoperazine, fluphenazine, haloperidol, and thiothixene, which have a strong, but purely psycholeptic, action. 

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